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Vitamins
Vitamin K1 and K2
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Special instructions
How to prepare for your test
Prepare for your Vitamin K (Nutritional) Blood Test by following these instructions. Do not eat or drink anything other than water for 12 hours prior to your test. If you take medication then you are allowed to take it as you would normally. Wrap your sample in foil immediately after it is taken.
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FAQs
How do you get vitamin K?
Most people get all the vitamin K they need through a varied and balanced diet. Because vitamin K is a fat-soluble vitamin, any vitamin K in the body that is not needed immediately is stored in the liver for future use. Green leafy vegetables, including broccoli and spinach, vegetable oils, and fortified cereals, are all good sources of vitamin K.
How common is vitamin K deficiency?
In the UK, for people who eat a healthy, balanced diet, vitamin K deficiency is rare. However, people with conditions that limit the absorption of dietary vitamins, such as biliary obstruction, coeliac disease, ulcerative colitis, and cystic fibrosis, can be at risk of vitamin K deficiency. Vitamin K supplements are available but monitoring the dose is important as too much can be harmful, so please speak with your doctor before supplementing vitamin K.
What is vitamin K?
Vitamin K refers to a group of fat-soluble vitamins that play a role in blood clotting, regulating blood calcium levels, and bone metabolism. In the liver, vitamin K helps supports prothrombin and factors VII, IX, and X, which are necessary for blood to clot properly.